A louvre window assembly typically comprises a plurality of louvres which are fitted in a frame. The louvres can move between a substantially horizontal open position and a substantially vertical closed position. The louvres are typically made of glass, although it is also known to have wooden or metal louvres. The louvres are typically rectangular, and will commonly have a length of between 40-100 cm and a width of between 10-30 cm, and the thickness of a few millimeters (for metal louvres) and typically between 4-8 mm for glass louvres.
A typical louvre window assembly will have between 5-25 louvres. Each louvre contains a pair of end clips typically made of plastic (although the older ones were made of metal). The surround frame contains a louvre operating mechanism. A typical louvre operating mechanism comprises a pair of long metal strips which are called operating bars. These metal strips are spaced apart typically between 5-40 mm and are positioned in a vertical part of the surround frame. The metal strips are operatively connected to a circular disk member, and one of the end clips is attached to the circular disk member. The metal strips can reciprocate with one metal strip moving upwardly and one metal strip moving downwardly and this movement causes the circular disk member to rotate, which causes the louvre to open and close. A handle is then attached typically to the metal strips and operation of the handle in an up-and-down manner operates the metal strips and therefore opens or closes the louvres. Because of the load on the system, a handle is typically used to operate between 4-10 louvres.
The present invention is directed, in one form, to a drive system which can operate the louvre system of the type described above.
It is known to provide an automated louvre system. For instance, it is known to provide an electric motor drive which drives the louvres via the protruding handle. That is, the drive is attached to the handle and is a “retrofit” kit. This arrangement is bulky and unsightly and is generally not suitable.
There are many considerations that must be taken into account when automating a louvre system. Firstly, if the louvre system will form part of an external louvre window assembly, security is an issue. To explain, a manually operated louvre system can be locked in the closed position in general by locking the handle closed.
In an automated system, it is advantageous to have an automated mechanism which can also ensure that the louvres can be locked in the closed position and cannot simply be forced back into the open position from the outside of the louvre window assembly. Thus, small drive motors have generally not been acceptable as the resistance in these drive motors is generally small and an intruder can force the louvre from the closed position to the open position which will simply cause rotation of the drive motor in the counter direction. Large drive motors with a high degree of resistance are unsuitable because of their size and cost.
However, there is an advantage in being able to conceal the drive motor and the mechanism that connects to drive motor to the operating bars in the vertical part of the louvre surround frame, and one way that this could be done is to conceal the drive motor within part of the louvre surround frame. However, to do so, the drive motor needs to be quite small.
It is also necessary to ensure that the louvre blades can be closed quite tightly together to ensure an acceptable level of resistance to water and air penetration between the louvre blades. In a manual system, this can be done by forcing the external handle to the closed position. However, this presents a difficulty if a concealed (and therefore small) drive motor is desired as the motor may not have enough power to apply sufficient load to the blades. The solution of simply having a large motor is not considered acceptable because of the size and cost.
It is known to provide a louvre door with a plurality of small wooden slats positioned within the door frame to provide ventilation. The wooden slats can be pivoted between the open and closed position by a pushrod and a pushrod is typically positioned substantially midway along the slats such that it can be pushed up-and-down manually. It is known to provide a drive motor which is concealed within the wooden frame and which operates the wooden slats, presumably by moving the pushrod. This drive motor can be made quite small and uses a range of cogs to convert the rotary motion to a linear motion. This type of arrangement would be unsuitable for a louvre window system and especially an external louvre window system which requires security and sufficient load on the louvres themselves to prevent ingress of water/wind etc. The drive motor is designed only to open and close the wooden slats, and there is no need to provide any additional security, loading etc.
It is also known to provide a window having a number of louvres which can pivot between an open and closed position, and a nonreversible motor which is attached to one of the operating bars that operate the louvres. The motor is connected to the operating bar in between the top and the bottom of the bar which means that the motor must be positioned in the vertical part of the louvre surround frame, and this part is quite “cluttered” already with the operating bars, the rotatable disk members and the like. Thus, to conceal the motor, it is necessary to make the vertical part of the louvre surround frame larger than normal which is not desired. Alternatively, the motor must at least slightly protrude from a smaller louvre surround frame which is also not desirable. Also, there is no apparent “locking” mechanism which can be operated by the motor, so security concerns do not seem to be overcome.
Another type of motor driven louvre arrangement is described in US patent application 2005/0120628. A motor is positioned within the vertical part of the louvre surround frame and is attached to one of the operating bars. However, it does not seem possible to “lock” the louvres in the closed position merely by operation of the motor. The motor is positioned in a vertical part of the louvre surround frame, and this places great constraints on the size of the motor.
It also seems to be known to provide a motor driven louvre arrangement where the louvres are interconnected such that rotation of one louvre rotates all the other louvres, and where the motor is operatively connected to one of the louvres.
Therefore, it is known to provide an automated louvre system, and it is known to provide an automated louvre system where a drive motor is positioned within the louvre surround frame. However, the problem of security, and the ability to provide an adequate load to the louvres does not seem to have been solved, and other difficulties also do not appear to have been solved.
It will be clearly understood that, if a prior art publication is referred to herein, this reference does not constitute an admission that the publication forms part of the common general knowledge in the art in Australia or in any other country.